The overall objectives of the Virology Core Laboratory are to provide ACTU investigators with quality-controlled laboratory services required for evaluation of clinical samples in the context of AIDS clinical treatment trials. this requires a well-organized, proficient HIV virology laboratory, a computerized specimen and data storage and retrieval system, and professional staff with expertise in HIV biology, molecular biology, and cell culture. Specific aims of the UAB ACTU Virology Core Laboratory will be: (i) To provide protocol-mandated testing of standard virologic markers (HIV-1 culture, p24 antigen, and ELISA and Western blot antibody analysis) for Birmingham and regional ACTU facilities. (ii) To participate in ACTG development, testing, and validation of additional surrogate markers such as quantitative determinations of plasma and PBMC viremia, acidified serum p24 antigenemia, and PCR (polymerase chain reaction) amplified total and circular viral DNA. (iii) To provide state-of-the-art cell and tissue separation and cryopreservation for optimal storage of clinical specimens for subsequent analysis. These specimens will be used for studies of surrogate markers, viral drug resistance, and other parameters relevant to improved diagnosis and treatment of HIV-1 infection and its sequelae. (iv) To participate in ACTG and internal quality-control/quality assurance programs to ensure accurate and efficient processing, analysis, cataloging, and retrieval of clinical specimens for protocol-mandated testing and developmental research. Results from ongoing basic and clinical studies are presented to demonstrate that the Birmingham site has the scientific expertise and experience to accomplish the stated aims and to provide a leadership role within the framework of the ACTG in the development of improved surrogate markers. Capability is demonstrated to perform 10,000 HIV-1 cultures and 40,000 antigen and antibody tests per year based on current laboratory activity. Finally, a close, interactive working relationship is demonstrated between the professional staff of the existing HIV laboratory and clinical investigators currently directing ACTG and non-ACTG sponsored clinical studies at UAB.